Yellowstone National Park was established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872, becoming the first national park in the U.S. Forty-four years after the establishment of Yellowstone, President Woodrow Wilson created the National Park Service, Aug. 25, 1916. A photograph of Old Faithful in Yellowstone National Park, 1870.
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